In this campaign threat, actors used botnets to breach websites using the vulnerability in the framework invoke function method to execute malicious code on the server.
“Cybercriminals use websites created using the PHP framework to breach web servers via dictionary attacks on default credentials and gain control of these routers for distributed denial of service attacks (DDoS).” reads Trend Micro blog post.
According to researchers, Yowai botnet has the same configuration table as like the Mirai variants and additionally adds the ThinkPHP exploit with other vectors.
Yowai carries out communication with command and control server over port 6 to receive commands and once it infects the router, then it launches a dictionary attack to infect other devices.
All the infected devices then turn to be a part of the botnet and the threat actors use the botnet to launch
Hakai and Yowai can easily be abused by cybercriminals to breach web servers and attack websites, researchers concluded.